Today is World Oceans Day, so here’s a collection of fun facts, marine research, and points to ponder about those big blue bodies.

Who needs sunlight? Life thrives even in depths that a ray of sunlight has never pierced. Miniature worlds pop up around vents in the ocean floor where heat escapes from the earth’s core. The water in the vent is hot – up to 300 degrees Celsius – but some bacteria can withstand the extreme heat. The buffet of bacteria then brings other sea life, such as crabs, to the underwater island. See this video from Planet Earth.

Say that again. All that boat motor noise is interfering with whale communication. Because of the whirring and the reverberating of the motors, the whales have to make louder calls to get themselves heard. Scientists continue to study both the short-term and the long-term effects of competing sounds in the water.

(Humpback Whale Tail; By Anne Smrcina, NOAA/SBNMS)

Seafood sales. Food labels don’t always tell the truth. Companies use buzz words such as ‘green,’ ‘sustainable,’ and ‘hormone free’ for their products even if those words don’t really apply. Make sure you know which labels you can trust and use shopping guides to make informed seafood purchases.

Hope sinks. The oceans used to be a point of hope since scientists thought that the large bodies of water would continue to steadily absorb vast amounts of carbon dioxide. The oceans are a crucial ‘carbon sink’ because they soak up and store a large percentage of the greenhouse gas that humans emit. New research, though, has found that the oceans are no longer increasingly taking up the gas. The sink has its limits.

Can you see me now? Camouflage can be crucial in the ocean. Cuttlefish, cousins to the octopus and squid, change their shapes to fit in with their surroundings. In these pictures, cuttlefish blend in with natural seaweed and sand, but also with artificial aquarium plants and striped wallpaper.

Also read:Fall Guys: When dead whales sink to the seafloor, their enormous carcasses give life to mysterious worlds inhabited by an assortment of bizarre creatures.Stepping Out: Masked by stinking anaerobic mud, fuggy heat, clouds of mosquitoes, and acre upon acre of flooded forest, mangroves are as mysterious as they are vital to our coasts. Looking for Admiral: North Atlantic right whales are in trouble, but it’s hard to know what to do about it